Dr Leach is an early career physician-scientist with specialty training in radiology and computational biomechanics, who seeks to continue developing his career within the VA health care system. Dr Leach’s long-term career goal is to use all of his clinical and research knowledge and expertise to comprehensively help patients and clinicians maximize wellbeing and prevent and alleviate suffering through improved understanding, diagnosis, and risk stratification of vascular diseases. To achieve this, Dr Leach seeks additional mentored training to further develop his knowledge and expertise in two key ways: 1) advancement of his scientific skills in imaging-based analysis of vascular disease that steps beyond anatomic characterization, to include compositional analysis, biomechanics, and biological features extracted from advanced imaging, and 2) leadership in clinical radiology and the vascular imaging research community. Improving management of abdominal aortic aneurysms (AAA) at both the patient and health care system levels necessitates new capabilities to distinguish aneurysms that will remain stable and clinically quiescent from those that will rapidly progressively enlarge and possibly rupture. To do this, we must step beyond the present paradigm of AAA surveillance, which involves no more than measuring the aneurysm size, and find ways to assess other AAA features that predispose to rapid progression. Dr Leach is perfectly positioned to pursue development of powerful new methods of AAA assessment, owing to his advanced scientific training and intimate familiarity with the complexity of AAA disease, its clinical management, and the simultaneous shortcomings of current imaging evaluation and impressive possibilities for future development. In this application, Dr Leach aims to combine his clinical expertise in vascular radiology and technical expertise in imaging-based biomechanical analysis of blood vessels to perform the necessary developments that will permit increasingly patient-specific geometric and biomechanical AAA analysis (Aims 1 and 2), multiparametric and multi-timepoint evaluation of AAA, and will culminate in a hypothesis-driven investigation of AAA features and their associations with aneurysm progression (Aim 3). [[Central to this work is careful testing and benchmarking of advanced MRI-based methods against the de facto standard CT-based methods of AAA assessment, to determine the appropriate balance between sophistication and precision and wide availability and cost.]] Dr Leach’s pursuit of these advancements necessitates close interaction with the community of radiologists and imaging researchers, vascular surgeons, and computer scientists at the VA, and provides a natural opportunity for Dr Leach to expand his leadership within that community. The proposed research and career development plan is expected to meaningfully advance our ability to comprehensively assess the progression risk of AAAs on a patient-specific basis...